Windshield wiper



Dec. 30, 1941. F. L. HILL arm.

WINDSHIELD WIPER Filed Nay 2.0, 1940 s S hee'ts-Sheet 1 J o G o 2 i 0 ao IIIIHI I I I I l l L Fl-l'llnllvllll I I I i I I l l l-Ml 'llll' 7 7 wIFIG.2.

FIG. 3.

' FIG. 4-.

C. F. THOMPSON BY/i/J ATTORNEY Dec. 30, 1941. F. L. HILL EI'ALWINDSHIELD WIFER Filed May 20, 1940 6 Sheets-Sheet 2 it v VI'NVENTORS F.L. HILL c. r. THOMPSON ATTORNEY F. L. HILL ET AL WINDSHIELD WILPER FiledMay 20, 1940 Dec. 30, 1941.

FIG. l0.

6 Sheets-Sheet 4 E INVENTORS F. L. Hl LL C. F. THOMPSON ATTORNEY I FiledMay 20, 1940 F. L. HILL ETAL WINDSHIELD WIPER 6 Sheets-Sheet 5 C. F.THOMPSON ATTOBNEY Dec. 30, 1941. F. L. HILL ETAL 2,268,253

WINDSHIELD' WIPER Filed May 20, 1940 6 Sheets-Sheet 6 FIG. I2.

mvemoas F. L. HILL C. F. THOMPSON BY ATTORNEY Patented Dec; 30, 1941WINDSHIEL-D WIPER Frank L. Hill, Garden Thompson, Westbury,

City, and Clifford 'r. N. Y., assignors to Air Associates, Inc., GardenCity, N. Y.

Application May 20, 1940, Serial No. 336,148

8 Claims.

This invention relates to mechanism for wiping a windshield, and fordistributing a fluid over the surface thereof.

On water supported or air supported boats that come into contact withsalt water spray there is a saline crystal formation which adheres tothe windshield obscuring or greatly reducing the degree or area ofvision. Also on airplanes in general there is an ice formation whichadheres to the windshield, which may form almost instantly due to thehigh rate of travel and the high altitudes encountered. The iceformation may be sorapid that where a wiper is in use the wiper bladewill adhere to the glass and stop the wiper, defeating the function ofthe apparatus. Other limitations of the present types of wipers in usefor boats and airplanes are the limited area whichlthey are eifective inand the lack of efficient operation.

According to the present invention, the formation of a saline crystalformation on a windshield is prevented by feeding a fluid to theeffected area of the windshield by means of a rapidly rotating wiperblade, thus permitting the wiper blade with the assistance of the fluidto clear an effective area of the windshield. The formation of ice isalso prevented by feeding an antifreeze fluid to the eil'ected area bymeans of a rapidly rotating wiper blade, thus distributing the fluidover the ice and eliminating the ice formation adhering to thewindshield. To prevent the wiper blade from adhering to the glass due toice formation, it is kept clear of the glass when inoperative, and ispermitted to move away from the'glass during operation to pass over anyobstruction such as ice formation. Thus the wiper blade movement isinsured under all reasonable conditions.

An object of the present invention is to provide a simple, compact andreliable apparatus for expeditiously clearing the windshield.

Another object of the present invention is to provide a simple andeffective device to feed a fluid to the windshield to thereby assist thewiper in clearing the surface thereof.

Another object is to provide a simple and effective means of insuringthe initial movement of the wiper blade.

Another object is to provide a simple and effective means of insuring acontinued operation .regardl'ess of obstructions on the windshield.

A further objectis to limit the distribution and application of the.fluid to the effective area ofthe windshield.

Another object is to distribute and apply a movement.

points of the blade wiping A still further object is to provide a wiperwhich may be moved to a position out of the field of vision.

Another object of the provide a wiper which tioned.

Another object is to wiper having a high rate of wiper blade travel.

Another object is to provide an oscillating wiper having anuninterrupted wiper blade movement.

Another object is to provide an oscillating wiper having a rotary wipingaction.

A still further object is to provide an oscillating wiper which inoperation distributes a fluid over the windshield by centrifugal force.

Another object is to provide a rotary wiper having an effective area ofoperating usefulness greater than the radius of the wiper blade.

Another object is to provide a power drive which, while driving a rotarywiper at a high rate of R. P. M., is at the same time driving the wholewiper assembly at a moderate oscillating rate.

Other objects and advantages will be apparent from the followingdescription when taken in conjunction with the accompanying drawingswherein: I

Fig. 1 is a side elevational view of one embodiment of the invention,installed in a windshield glass;

Fig. 2 is a top plan view and holder;

Fig. 3 is abottom wiper blades;

Fig. 4 is an end view of the holder for wiper blades;

fluid at the point or present invention is to may be adjustablyposiprovide an oscillating of the wiper blades plan view of the holderfor Fig. 5 is a cross-sectional. view of the driver;

head and fluid distributing means;

Fig. 6 is a cross-sectional view of the wiper blade mounting assembly;

Fig. 7 is a cross-sectional viewtaken on line 1-1 of Fig. 6;

Fig. 8 is a detail illustrating the cam arrangement for lifting thewiper blades;

Fig. 9 is a cross-sectional view of the wiper blade and head assembly inanother embodiment of the invention;

Fig. 10 is a cross-sectional view of the base assembly which supportsand operates the structure illustrated in Fig. 9;

Fig. 11 is a front ele ational view of the base assembly;

throughout the various views, the one embodia ment illustrated in Fig. lis provided with two interconnected sets of mechanism 20 and 2|, oneupon each side of a windshield 22. The mechanism 20 is more definitelydefined in Fig. and comprises a housing 23 wherein two drive assemeblies 24 and 25 are mounted by a screw threaded insertion. Also mountedto thehousing ha fluid carrying line 26 which is connected within thehousing 23 by means of a duct 21 to a fluid sealed chamber 28, the sealbeing maintained by sealing washers 29 and 30. The drive assembly 24comprises an externally threaded bearing member 3| which is secured tothe housing 23.

Within the bearing 3| a long shank bevel pinion gear 32 is mounted andheld against vertical thrustby a lock nut 33. Mounted within the longshank bevel pinion gear 32 is the square end 34 of a flexible cable 35.The drive assembly comprisesa pinion gear 36 keyed to a shaft 31 andheld in fixedrelationship with the shaft by a lockwasher and nut 38against a shoulder 39 of the shaft 31. The shaft 31 is mounted in abearing. 40 which is in turn mounted in an externally threaded casting4|, the casting 4| being threadably secured'to the casting 23. The shaft31' is also 'mounted in a roller bearing 42, the bearing in turn beingmounted in the casting 23.

The bearing 42 is pressed into the. casting 23 against the fluid sealingwasher 30, and the end of shaft 31 has another fluid sealing washer'29which abuts the washer 30, all forming a fluid seal for the shaft 31 andthe chamber 29. The shaft 31 has a central bore 43 leading from thechamber 28 to a point 44 which should be slightly I beyond the outeredge of the casting 4| when it is drawn up to its set relationship withthe main casting 23. At the point 44 two oppositely disposed holes 45and 46 are drilled from the exteriorof the shaft 31 to the internal boreThe holes are radial but preferably with a slight cant. The function ofthis internal passage will be explained hereafter. Also positioned inthe extended solid'portion of the shaft 31 is a pin 41, which is reallya part of the assembly 2|. The mechanism 2| is more definitely definedin Fig. 6 and comprises a sleeve member 48 which is rotatably mounted onthe shaft 31, but limited in its degree of rotation by the pin 41 andguided in its thrust or lengthwise movement by the angular cam slot 49in the sleeve in which the pin 41 is positioned. A hearing member 50 ismounted on the sleeve 48, and'ha's'an extended cup shaped portion 5|integrally cast therewith. The cup shaped portion 5| has two oppositelycut keyways 52 and 53 in the periphery thereof. Mounted on the sleeve 48is an overload release spring 54 which is adjustably compressed againsta shoulder 55 of the casting 50 by a screw collar 58 with a set pin 51.Mounted-on an externally threaded portion 58 of the cup shape end 5| ofthe bearing member 50 is another cup shaped member 50 which isthreadably secured thereto and may be locked in a particular position bya ring locking member 6| whose end 62 is inserted through a hole in thecup shape member 80 and fitted into either the slot 52 or 53 as the caseFitted within the cup shaped member 63 having two circumferential maybe. is a cam piece cam formations 64 and a shoulder 86 on which 7 twooppositely disposed key projections 81 and II are integrally cast, aflat rear bearing face 10, and a hollow central bore 1| which goescompletely through the cam piece 63. The sleeve 48 has two can'i tips 12and 13 formed integrally therewith and so positioned that they normallyfit into the two circumferential cam formations 64 and 85. Thus thescrew collar, after being adjustably set, will cause the spring 54' tobear against the bearing member 50 tending to thrust it to the rightaxially, but threadably securedto thernember 50 is a cup shape member 50which bears against thecam, piece 63 and the cam piece in, turn bearsagainst the end of the sleeve member 48. Since the screw collar 5|i issecured to the sleeve member 48 and the whole assembly is spring pressedagainst the end of the sleeve member 48, the whole assembly will remainin a fixed relationship to the sleeve member 48,. exe cept when thespring 54 is compressed in operation. Also fitted within the cup shapedmember 60 is a spring 15 which normally holds the whole assembly 2 l'inan inoperative positionwith the pin 41 acting as a stop for the rightextremity of the slot 49. The spring 15 is compressible between theinner portion of the cup shaped member 60 and the end of the shaft 31.Also mounted on and movable with the bearing member 50 is a wiper bladeholder 16, so that the drive transmitted by the shaft 31 and pin 41causes the pin to ridedownthe slot 48 to the left extremity and thusdrive the blade holder 18. and assembly 2| rotatively, and at the sametime cause an axial movement of the assembly and. blade holder to theright. Referring back toFig. 1, it is apparent that the blade holder18has a few holes in its outer extremities which permit the blade to bemountedat its center of gravity,

of the blade. Due to the rotary movement of; the wiper, the two extendedarms of the wiper blade holder are slightly canted as illustrated inFig. 4 to insure a wiping contact of the blade with the glass. Theholder comprises two U-shaped. arms extending in opposed relationshipfrom a common hub. The hub portion has two angularly disposed pieces 11'and 18 between the outer walls of the U-shaped holder.

Suitable means not shown are provided to rotate the flexible shaft 35 ata high rate of R. P. M. such as 1,000 to 2,500.

A fluid is controllably fed to the outside of the windshield into. thehub portion of the wiper holder 15. For this purpose the shaft 31 ishollow through a portion of its length, being open at one end thereofand hollow as far as the twov ports 45 and 46. The open end of the shaft31 is positioned in the sealed chamber 28, this chamber being connectedto a supply line 26 by means of a duct 21, so that any desirable fluidmay be employed; for instance, an anti-freeze mixture of glycerine andalcohoL' The flow of this fluid is controlled bya valve or other meansnot shown- In operation, the fluid flows through the ports 45 and 46,spurts into the hub portion of the .wiper holder, then the centrifugalforce carriesv it up the angularly disposed pieces 11 and 18 to thelower portion of the leading edge of the According to the presentinvention.-the wiper bladeswill remain clear oi-the glass 22, due to theforce of the spring 18, as long asthe device is inoperative. but as soonas the shaft 31 is driven at a high rate of speed. the torque throughthe pin 41 works against the spring and forces the sleeve 48 backwardwhich in turn moves the wiper backward to contact the glass, which isthe normal operating position. Thus it is apparent that when the wiperis inoperative, the wiper blade will be clear of. the glass asillustrated in Fig. l, and when the wiper is operated the wiper bladewill be moved backward to contact the glass with a slight pressure whilerotating thereon.

In the event the wiper is not operated in time to prevent irregularformations of ice or snow upon the windshield, the normal effect ofstarting the wiper and contacting the irregular surface of thewindshieldmight produce a large torque on the drive shaft, perhapssufficient to prevent the wiper from rotating and thusdefeat itsfunction of spreading an anti-freeze fluid and wiping away the film orcoating on the glass. To overcome I this difflculty, the presentinvention includes means to permit the wiper blade to pass over anyobstruction on the glass surface andthus spread theanti-freeze fluidthereon, which also assists the blade in removing the film or coating orobstruction as the case may be. .More specifically, when the sleevemember 48 on which the wiper comprises a housing I23 wherein two driveasv semblies I24 and I are mounted. Also conblades are mounted movesbackward to an operative position so that the wipers are in contact withthe glass surface, the blades are exerting a slight pressure against theglass surface. The

instant that this pressure is increased due to some obstruction, thesleeve member 48 will continue to rotate, but at the same time the wiperblade will be slightly retarded by the obstruction. The effect of thisretardation will be a radial misalignmentbetween the sleeve 48 and, thebearing member 50 on which the wiper blades are mounted. The bearingmember 50 carries with it the cam member 63 which is locked to it forrotative movement, whereas the sleeve member 48 has two cam tips 12 and13 which are an integral part thereof and rotate therewith. It may befollowed referring to Fig. 8 that the cam 63 has two circumferential camformations .64 and 65 that are spring pressed against the cam tips 12and 13. Therefore, it is apparent that any radial misalignment willcause the cam tips to move up on the cam faces as illustrated in Fig. 8.This causes the whole assembly 2| to move outwardly from the shaft 31against the compression resisting spring 54, thus permitting the wiperblade to pass overrwhatever obstruction was retarding its rotation. Itis apparent that under most circumstances the overload torque will beslight permitting the blade to pass over the obstruction and resume anormal load torque for operation.

In another embodiment of the present invention,wherein all the featuresof the embodiment already disclosed are retained and certainmodiilcations introduced, there is a single assembly of the mechanismI00 mounted at some appropriate point not shown sothat the wiper bladesare positioned slightly in front of the windshield glass as illustratedin Fig. 9 and free to oscillate in a given path as illustrated in Fig.12. The mechanism I00 is more definitely defined in Figs. 9, 10, 11 and12 and comprises a head assembly IN, a base assembly I02 and aninterconnecting shaft unit I03. The base assembly I02 is revolvablymounted in a bearing I04 which is part of a supporting arm I05. The headassembly IOI nected to a passage I21 in the housing I23 is a fluidcarrying line I28. The duct I21 communicates with a fluid sealed chamberI28, the seal being maintained by sealing washers I28 and I30. The driveassembly I24 comprises a bearing member I3I which is positioned withinthe housing I23 and held in a fixed position by means of a shoulder II9of the bearing member I3I being clamped between the housing I23 and theend I I8 of the shaft unit I03. The end H8 i clamped against the housingI23 by means of a nut I I1 which has a shoulder I I6 which bears againstthe shoulder II5 of the shaft end H8. The nut H1 is threadly secured tothe lower external portion of the housing I23. Within the bearing I3I along shank bevel pinion gear I32 is mounted and held against verticalthrust by a lock nut I33. Mounted within the long shank pinion gear I 32is the square end I34 of a shaft I35. The drive assembly I25 comprises abevel gear I36 keyed to a sleeve I48, which i in turn rotatably mountedon a hollow shaft I31. The shaft is held in a fixed relationship bymeans of a spring I54,

screw collar I56, and the pins I41, I41. The pins I41 are mounted in theshaft I31 and extend into two oppositely lfocated angular slots in thesleeve I48. The whole assembly I25 is mounted in the housing I23, bymeans of a bearing I42 and a bearing I40. The bearing I40 is mounted inan externally threaded casting MI. The casting is threadably secured tothe housing I23. The open end II4 of the hollow shaft I31 is suspendedin the chamber I28 so that the anti-freeze fluid therein may be forcedthrough the hollow shaft. The opposite end I I3 of the shaft I31 is inclose proximity to the windshield glass 22 and has two oppositelypositioned ports I45 and I46 in the end thereof. A wiper assembly H2 ismounted on the end II3 of the shaft I31, and restrained from axialmovement by a spring I15 which is compressed between a shoulder I33 oftheshaft I31 and the hub portion I60 of the wiper holder I16. The wiperholder is positioned by a cam piece I63 pinned to the end H3 of theshaft I31. The cam piece I63 has two oppositely formed cam faces I64 andI65 wherein two solid pins I12 and I13 are positioned. The pins I12 andI13 are mounted in the hub portion I60 of the holder I18 by a drive fitso that they are fixed with relation thereto. The opposite end ofthepins I12 and I13 are rounded to reduce the bearing area of the pinson the cam faces I64 and I65. When the shaft I31 is inoperative, thepins I12 and I13 and the cam I63 are the means of restraining the wiperassembly II2 from rotative movement, but when the shaft I31 is driventheassembly functions as the driving means, but also permits the wiperassembly II2 to move axially under an overload torque such as producedin the wiper assembly when the wiper blades are restrained by anobstruction on the glass 22. In the event an overload torque isproduced, the assembl I I2, by means of the pins I12 and I13, will moveto the left as illustrated in Fig. 9, the pins riding up on the camfaces I64 and I65. When the cause of overload torque is passed over orovercome. the spring I15 will return the assembly to its originalposition with the pins I12 and I13 in the center of the cam faces I64and I65.

Referring now to the connecting assembly I03, we have a hollowcylindrical member I06 which is threadablysecured to theend piece I I8which, when assembled, is clamped to the head assemgear I88 meshing withthe worm I85.

4 I accepts bly. IOI'.- The connecting assembly I03 is primarily asupporting member and being hollow permits the shaft I35 and the fluidcarrying line I26 to pass therethrough. The opposite end of the hollowmember I06 is also threadably secured to an end piece I80 which issimilar to the end piece H8. The end piece I80 is clamped to an upperthreaded portion I8I of the base assembly I02 by a clamp nut I82. Ashoulder I83 of the assembly I03 is held'by a shoulder I84 of the clampnut I82.

Referring now to the base assembly I02, it is comprised of a housing I85which is threadably secured to a supporting-shaft I86, which is in turnrotatably mounted in the bearing I04 and locked against axial movementby a nut and lock washer I81 which retains the shoulder I88 of the shaftI88. against the bearing I04. Mounted within the shaft I88 is a longshank bevel pinion gear I88 which is locked against axial movement by ascrew collar I80 on the end of the shank of the gear. Mounted within thepinion gear is the square end 34 of the flexible shaft 35. Thus theassembly I02 is rotatably mounted and se curely supported for operation.Also mounted within the housing I85 is a drive assembly I24 mounted onthe shaft I35 between bearings I8I and I82. A portion I83 of the shaftI35 is square and fits within, a long shank bevel pinion gear I36. Thusthe drive from shaft 35, bevel pinion I88, to bevel gear I36 with whichit meshes, is

. transmitted to the shaft I35 by means of the square shank portion ofthe shaft which keys into a square hole in the gear I36. The bevel gearI38 is rotatably mounted within the bearing I8I and locked against axialmovement by a screw collar I84. Also mounted on the shaft I35 at itslower end is a worm I85 which is pinned thereto. The end of shaft I35 ismounted in the bearing I82 and locked thereto by means of a screw collarI86. The bearing I82 is in turn mounted in a casting cover I81 and heldin a fixed relation- Lgship by means of a snap ring I88. The castingcover I81 is bolted to the main base housing I85.

Also mounted within the housing I85 is a worm The worm gear is mountedon and pinned to a shaft 200, and the shaft is in turn mounted betweentwo bearings 20I, 202 in the housing I85. The outer end of the shaft 200has a fiat disc 203 of fairly large radius. keyed thereto, and mountednear the periphery of the disc is a pin 204 which may be secured thereinby a drive fit. The pin 204 has a link arm 205 which is rotatlvelymounted thereon and retained in that relation by a washer and nut 208.Also mounted in the upper end of the housing I85 is the fluid carryingline I26 which connects with a passage or duct 201 which in turnconnects with a fluid chamber 208. The supply line 2 I8 is connected tothe fluid chamber 208. The fluid chamber 208 is formed as a recesswithin a collar 2 I0 which is mounted on a hub 2 II of the housing I85and retained in fixed relation with the housing. To insure the fluidseal of the chamber 208 there are two sealing washers 2I2 and 2I3 withinthe recess of collar 2I0.

Referring to Figs. 9,10' and 11, it is apparent that when the flexibleshaft 35 is driven by a motor or other means not shown, the bevel pinionI88 will also be driven, the gear I88 in turn driving the gear I36 withwhich it meshes. Since the gear I36 is keyed to the shaft I35 by thesquare shank I83 it will drive the shaft I35 also. The shaft I35 will inturn drive the bevel pinion I32 Fig. 9 to which it is keyed by thesquare shank end I34. The bevel pinion I32 will in turn drive the bevelgear I38 with which it meshes. Since the bevel gear I38 is keyed in thesleeve I48, the sleeve will be driven with the gear. Since the sleeveI48 has two oppositely positioned angular slots in its periphery throughwhich pins I41, I41 are positioned, any clockwise rotation (as viewedfrom the right hand side) will cause the pins to ride up the cam slotagainst the compressive force of the spring I54. Thus as the torqueincreases. the shaft I31 will move axially to the right and at the sametime the shaft will be driven in a clockwise direction by the sleeveI48. When rotation ceases, the force of the spring I54 will cause thepins I41, I41 to move down .the cam slot. which at the same time movesthe shaft axially to the left to its initial position. It is readilyseen that movement of the shaft I31 to the right will carry the wiperassembly II 2 to the right and bring the wiper blades in contact withthe glass 22 with a slight pressure to insure a wiping action. Duringthe rotation of the blades, if

position when the excessive torque has been eliminated.

Referring to Figs. 10 and 11, since the shaft I35 is driven it will inturn drive the worm I85 and that will in turn drive the worm gear I88.Since the worm gear I88 is keyed to the shaft 200,

the shaft will be driven and the disc 203 which is keyed thereto.Referring to Fig. 11, it is apparent that the disc 203 will carry thepin 204 in a circular path, and since the pin 204 is mounted in the linkarm 205 the arm must move with the pin. Referring to Fig. 12, the linkarm 2051s pivotly affixed at a point 206 in a slot 201. Since the pivotpoint 206 is a fixed point and the assembly I02 is mounted in a fixedbearing I04, the eccentric pin 204 when driven through its circular pathwill first lengthen, then shorten the effective crank arm causing anoscillating motion to the assembly I02 about the bearing I04. Since theassemblies I03 and IOI are affixed to the base assembly I02, then thewhole mechanism I00 will oscillate. The degree of oscillation will bedependent upon the size of the disc 203 or rather the radius of the pin204 from the center of the i disc 203 and the distance from the centerof oscillation (the center of the bearing I04) to the center of the disc203. In the particular example illustrated herein as in Fig. 11, thereis an approximate range of 50 of oscillation, which is also graphicallyshown in Fig. 12 wherein the member I03 oscillates between points M andN. It is readily apparent that the member I03 may be oscillated agreater or lesser amount as between points X and Z by varying theeffective I02 and to some fixed point in the outer structure not shown.

The useful area treated in both embodiments of the present invention isgraphically illustrated in Figs. 12 and 13. In Fig. 12 the area may bevaried by changing the effective crank arm, whereas in Fig. 13 the shaft21 being fixed, the area treated is dependent upon the size of bladeused and becomes a fixed area for all purposes.

The application of the present invention as illustrated in Fig. 13 willpermit the highest degree ,of efficiency over the area treated and atthe same time effect a radiating area about the point 31 when theanti-freeze fluid is being used, whereas the embodiment illustrated inFig. 12 will permit a greater area of treatment with perhaps a slightlylesser degree of effectiveness under extreme conditions.

The embodiment of the invention herein disclosed is merely illustrativeand may be modified and de'parted fromin many ways without departingfrom the spirit and scope of the invention as pointed out in and limitedsolely by the,

appended claims.

What is claimed is: 1. A windshield wiper comprising, in combination, awiper blade mounted'in the Windshield so that the wiper blade is closeto but not in contact with the surface thereof, means including portsnear the inner end of said blade for feeding liquid to the inner endof'the blade, means to drive the wiper blade rotatably, means to permitthe, wiper blade to move into contact with the surface of the windshieldwhen the wiper blade rotation starts, means to distribute the liquidfrom the said ports near the inner end of the blade over a predeterminedarea bycentrifugal force, means to allow the wiper blade to move awayfrom the windshield surface momentarily when an obstruction to itsrotation is encountered although still distributing the fluid, and meansto remove the wiper blade from the windshield surface when rotationstops.

. 52. A windshield wiper comprising, in combination, a wiper blademounted near the windshield so that the wiper blade is close to but notin contact with thesurface thereof, means including ports near the innerend of said blade for feeding liquid to the inner end of, the blade,means to drive the wiper blade rotatably and oscillatory, means topermit the wiper blade to move into contact with the surface of thewindshield when the wiper blade rotation starts, means to distribute theliquid from the said ports near the inner end of the blade over apredetermined area by: centrifugal force, means to allow the wiper bladeto move away from the windshield surface momentarily when an obstructionto its rotation is encountered although still distributing the fluid,and means to remove the wiper blade from the windshield surface whenrotation stops.

3. A windshield wiper comprising driving means, a, shaft, means totransmit a rotary movement and, when the rotation starts, also a limitedaxial movement from said driving means to said shaft, a rotary wiperblade, and an overload coupling between said shaft and said wiper blade,said coupling including means to impart to said wiper blade an axialmovement in a direction opposite to that of the first-mentioned axialmovement when said wiper blade encounters an obstruction.

4. A windshield wiper comprising driving means, a shaft, means totransmit a rotary movecounters an obstruction, and means to reverse saidaxial movements when rotation stops and when said blade has passed saidobstruction respectively.

5. A windshield wiper as claimed in claim 4 further comprising alongitudinal member in the one end of which said wiper shaft isjournalled, a pivot near the other end of said longitudinal member andabout which said member is oscillatable, and a device to oscillate saidlongitudinal member and to swing said member with said wiper out of theusers vision, said device comprising a crank drive mounted near saidother end of said member and a connecting rod, one end of said rod beingconnected to said crank and the other being adjustable as to the spacingof a point to which it may be secured from said pivot.

,6. A a windshield wiper comprising driving means, a hollow shaft havingan open end and a closed end, a housing in which said open shaft end isaxially movable, means including a cam device to transmit a rotarymovement and, when rotation starts, also a limited axial movement fromsaid driving means to said shaft, a rotary wiper blade, an overloadcoupling between said shaft and said wiper blade, said couplingincluding another cam device to impart to said blade an axial movementin a direction opposite to that of the first mentioned axial movementwhen said wiper blade encounters an obstruction, means to admit ananti-freeze fluid to said chamber and the interior of said shaft andports in said shaft near said wiper blade to feed said fluid from theinterior of said shaft to anarea wiped by said blade.

'7. A windshield wiper comprising a driving shaft, a sleeve, means totransmit rotary movement from said driving shaft to said sleeve, saidsleeve being provided with a slot inclined with respect to the sleeveaxis,. a driven shaft interiorly of said-sleeve and including a pin inengagement with said slot, 2. second sleeve mounted on said drivenshaft, a wiper blade secured to said second sleeve, and a cam and aspring connection between said second sleeve and said shaft, wherebysaid second sleeve will be axially shifted in relation to said shaftwhen said wiper blade encounters an obstruction to its rotation duringthe rotation of said driven shaft.

8. A windshield wiper comprising a driving shaft, a sleeve, means totransmit rotary movement from said driving shaft to said sleeve, saidsleeve being provided with a slot inclined with respect to the sleeveaxis, a driven shaft interiorly of said sleeve and including a pin inengagement with said slot, at wiping means rotatably mounted on saiddriven shaft, and a member secured to said driven shaft and includingcam faces projecting therefrom in axial direction, said wiping meansincluding projections in engagement with said cam faces, and a spring soarranged as to urge said wiping means against said cam faces.

FRANK L. HILL.

CLIFFORD F. THOMPSON.

